1. Field of the Invention
The present invention relates to a display device, and in particular, to a small flat-panel display device that has a large display region with respect to a small overall size.
2. Description of the Related Art
In view of flat and lightweight, liquid crystal displays or organic EL displays are used for various purposes in various fields. In mobile phones or DSCs (Digital Still Camera), small liquid crystal displays or organic EL displays are widely used. These display devices need to have an overall size as small as possible. Meanwhile, in terms of ease of viewing, a display region is preferably sufficiently large. Therefore, there is a need for a display device that has a small overall size but a large display region.
A liquid crystal display has a TFT substrate, on which pixels each having a pixel electrode and a thin film transistor (TFT) are arranged in a matrix, a counter substrate that is opposed to the TFT substrate and has formed thereon color filters, and a liquid crystal layer that is interposed between the two substrates. The liquid crystal layer is sealed by a sealant, which is formed at the periphery between the TFT substrate and the counter substrate. The counter substrate has a counter electrode, which is formed to be opposed to the pixel electrodes of the TFT substrate. An image signal is applied between the pixel electrodes and the counter electrode, and transmitted light from a backlight or reflected light of external light is controlled for each pixel, thereby forming an image.
A common voltage is applied to the counter electrode of the counter substrate. The common voltage is supplied to a terminal portion of the TFT substrate, and is then supplied to the counter electrode of the counter substrate through a common wiring line of the TFT substrate. Accordingly, it is necessary to electrically connect the common wiring line of the TFT substrate and the counter electrode of the counter substrate. The electrical connection of the common wiring line of the TFT substrate and the counter electrode of the counter substrate is made by forming a conductive paste between the TFT substrate and the counter substrate. For example, a conductive paste, in which conductive beads are dispersed in a resin paste, is used. JP-A-2001-21909 discloses a technology that electrically connects the TFT substrate and the counter substrate by the conductive paste containing conductive beads.